Fungicidal mixtures

ABSTRACT

A liquid concentrated fungicidal composition containing a fungicidally acceptable carrier and/or surface active agent and synergistically effective amounts of 
     (a) at least one acrylic acid morpholide of formula I ##STR1##  in which R 1  and R 2  have the meaning given in claim 1, and (b) at least one fungicidal N-pyridylaniline compound. This invention also includes a method of controlling the growth of phythopathogenic fungi at a locus which comprises applying synergistically effective amounts of at least one acrylic acid morpholide of formula I and at least one fungicidal N-pyridylaniline compound to the locus.

This application claims the benefit of U.S. provisional application Ser.No. 60/085,349, filed May 13, 1998.

BACKGROUND OF THE INVENTION

The present invention includes a fungicidal composition comprising afungicidally acceptable carrier and/or surface active agent andsynergistically effective amounts of at least one compound of formula I,and at least one N-pyridylaniline compound.

Fungicidal N-pyridylaniline compounds are known for example from EP 0031 257. The International patent application WO 95/04460 suggest toprepare fungicidal water dispersible granules containing3-chloro-N-(3-chloro-5-trifluoromethyl-2-pyridyl)-2,6-dinitro-4-trifluoromethylbenzeneand optionally other fungicidal compounds including dimethomorph.

However, until now it has not been known that the compounds of formula Iwith N-pyridylaniline compounds, when admixed in a tank mix or whenco-formulated, would show synergistic effects. Moreover, it has not beenknown that a liquid concentrated composition comprising a synergisticmixture of these compounds can be advantageously be used for controllingdiseases caused by oomycetes, e.g. Phytophtora infestans.

A mixture of fungicides shows synergistic effect if the fungicidalactivity of the mixture is larger than the sum of activities of theseparately applied compounds. The expected fungicidal activity for agiven mixture of two fungicides can be calculated as follows (See Colby,S.R., "Calculating synergistic and antagonistic response of herbicidecombinations", Weeds 15, pp 20-22 (1967):

    EE=x+y-x·y/100

wherein

x is the efficacy in % compared with an untreated control upon treatmentwith a fungicidal active ingredient A at a dose rate a;

y is the efficacy in % compared with an untreated control upon treatmentwith a fungicidal active ingredient B at a dose rate b;

EE is the expected efficacy with a combination of fungicidal activeingredients A and B at a dose of a+b, respectively.

If the actual efficacy (E) exceeds the expected (calculated) one (EE),the mixture displays a synergistic effect.

SUMMARY OF THE INVENTION

The present invention includes a liquid concentrated fungicidalcomposition comprising a fungicidally acceptable carrier and/or surfaceactive agent and synergistically effective amounts of

(a) at least one acrylic acid morpholide of formula I ##STR2## in whichR¹ and R² each independently represent hydrogen or halogen atom or anoptionally substituted alkyl, alkoxy, alkenyl, alkynyl, alkadienyl,aryl, aryloxy, heteroaryl, cycloalkyl, cycloalkenyl, bicycloalkyl orheterocyclyl group,

(b) and at least one fungicidal N-pyridylaniline compound.

The fungicidal compounds of formula I to be used according to thepresent invention are known from European patent application EP 0 120321.

The present invention also includes a method for controlling the growthof phythopathogenic fungi comprising application of synergisticallyeffective amounts of at least one compound of formula I and at least oneN-pyridylaniline compound as defined above.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Surprisingly, a strong synergy between the compounds of formula I andN-pyridylaniline compounds was found when these two compounds were tankmixed or co-formulated, compared to the activity of each compound in asolo formulation.

In general terms, unless otherwise stated, as used herein the termhalogen atom may denote a bromine, iodine, chlorine or fluorine atom,and is especially a bromine, chlorine or fluorine atom, in particular abromine or chlorine atom.

Optionally substituted moieties may be unsubstituted or have from one upto the maximal possible number of substituents. Typically, 0 to 2substituents are present. Each optionally substituted groupindependently may be substituted by one or more halogen atoms or nitro,cyano, cycloalkyl, preferably C₃₋₆, cycloalkyl, cycloalkenyl, preferablyC₃₋₆, cycloalkenyl, haloalkyl, preferably C₁₋₆ haloalkyl,halocycloalkyl, preferably C₃₋₆ halocycloalkyl, alkoxy, preferably C₁₋₆alkoxy, haloalkoxy, preferably C₁₋₆ haloalkoxy, phenyl, halo- ordihalo-phenyl or pyridyl groups.

Unless otherwise stated herein, the terms alkyl, alkenyl, alkynyl,alkadienyl and alkoxy as used herein with respect to a radical or moietyrefer to a straight or branched chain radical or moiety. As a rule, suchradicals have up to 10, in particular up to 6 carbon atoms. Suitably analkyl or alkoxy moiety has from 1 to 6 carbon atoms, preferably from 1to 5 carbon atoms. A preferred alkyl moiety is the methyl, ethyl,n-propyl, isopropyl or n-butyl group.

Unless otherwise stated herein, the term aryl, as used herein withrespect to a radical or moiety refers to an aryl group having 6, 10 or14 carbon atoms, preferably 6 or 10 carbon atoms, in particular phenylbeing optionally substituted by one or more halogen atoms, nitro, cyano,alkyl, preferably C₁₋₆ alkyl, alkoxy, preferably C₁₋₆ alkoxy, haloalkyl,preferably C₁₋₆ haloalkyl, haloalkoxy, preferably C₁₋₆ haloalkoxygroups.

Unless otherwise stated herein, the term cycloalkyl or cycloalkenyl, asused herein with respect to a radical or moiety refers to a cycloalkylgroup having 3 to 8 carbon atoms or a cycloalkenyl group having 5 to 8carbon atoms, preferably 5 to 7 carbon atoms, in particular cyclopentyl,cyclohexyl or cyclohexenyl being optionally substituted by one or morehalogen atoms, nitro, cyano, alkyl, preferably C₁₋₆ alkyl, alkoxy,preferably C₁₋₆ alkoxy.

Unless otherwise stated herein, the term heteroaryl, as used herein withrespect to a radical or moiety, refers to an aromatic heterocyclic grouphaving 5 or 6 ring atoms selected from carbon, nitrogen, oxygen andsulfur, at least one of which being nitrogen, oxygen or sulfur beingoptionally substituted by one or more halogen atoms, nitro, cyano,alkyl, preferably C₁₋₆ alkyl, alkoxy, preferably C₁₋₆ alkoxy, inparticular azolyl, triazolyl, triazoly, furanyl, oxazolyl, thienyl,thiazolyl, dithiazolyl, pyridyl or pyrimidyl.

Unless otherwise stated herein, the term heterocyclyl, as used hereinwith respect to a radical or moiety, refers to a non-aromaticheterocyclyc group having 5 or 6 ring atoms selected from carbon,nitrogen, oxygen and sulfur, at least one of which being nitrogen,oxygen or sulfur being optionally substituted by one or more halogenatoms, nitro, cyano, alkyl, preferably C₁₋₆ alkyl, alkoxy, preferablyC₁₋₆ alkoxy, in particular tetrahydropyranyl, tetrahydrofuranyl,tetrahydrothienyl, tetrahydropyridyl or tetrahydropyrimidyl.

Preferred compounds of formula I are those in which R¹ and R² aredefined as follows:

    ______________________________________                                                  R.sup.1       R.sup.2                                               ______________________________________                                        a)          Cl              H                                                 b)          Br              H                                                 c)          CF.sub.3        H                                                 d)          CF.sub.3 O      H                                                 e)          propyl          H                                                 f)          butoxy          H                                                 g)          phenyl          H                                                 h)          4-chlorophenoxy H                                                 i)          H               3-phenoxy                                         ______________________________________                                    

Particularly preferred compounds of formula I are those wherein R¹represents a halogen atom and R² represents a hydrogen atom.

A particularly preferred compound of formula I is dimethomorph, which isdescribed in the "The Pesticide Manual", 10th Edition, The British CropProtection Council and The Royal Society of Chemistry, 1994,(hereinbelow abbreviated as "Pesticide Manual"), page 236.

Preferred N-pyridylaniline compounds are the compounds of formula II,##STR3## wherein R³ and R⁴ each independently represent a hydrogen orhalogen atom or an optionally substituted alkyl group, preferably chloroor trifluoromethyl;

Y each independently represents a halogen atom or an optionallysubstituted alkyl group, preferably chloro or trifluoromethyl;

m is 0 or an integer of 1, 2, 3 or 4, preferably 2.

The following compounds of formula II are preferred:

    ______________________________________                                        R.sup.3      R.sup.4        (Y).sub.m                                         ______________________________________                                        a)      CF.sub.3 Cl             3-Cl 5-CF.sub.3                               b)      CF.sub.3 Cl             3-Cl 5-Cl                                     c)      CF.sub.3 H              3-Cl 5-CF.sub.3                               d)      CF.sub.3 H              3-Cl 5-Cl                                     e)      CF.sub.3 2-hydroxyphenoxy                                                                             3-Cl 5-CF.sub.3                               f)      CF.sub.3 ethoxy         3-Cl 5-CF.sub.3                               ______________________________________                                    

A particularly preferred compound of formula II is fluazinam, which isdescribed in the "The Pesticide Manual", page 474.

Preferred fungicidal compositions of this invention include liquidconcentrated co-formulations comprising the following constituents:

a surface active agent;

an acrylic acid morpholide of formula I, in particular dimethomorph;

at least one N-pyridylaniline compound; in particular fluazinam,

optionally a foam breaking agent, in particular a mixture ofperfluoroalkyphosphonic acids and/or perfluoroalkylphosphinic acids, inparticular Defoamer® SF or Fluowette® PL, which are commerciallyavailable from Clariant GmbH, Germany.

The compounds of formula I and the N-pyridylaniline compound are to beapplied together, in synergistically effective amounts. They exhibit anextraordinary efficacy against a broad range of phytopathogenic fungi.They are systemic and may be applied as leaf or soil fungicides.

The mixture according to the invention may be preferably applied forcontrolling diseases caused by phytopathogenic fungi of the genera ofPhythophthora, Plasmopara, Pseudoperonospora, Bremia, Peronospora,Altemaria, Guignardia, Septoria, Botrytis, Phomopsis, Rhizoctonia, andin particular of the species Phythophthora infestans and Plasmoparaviticola.

The preferred application rate of the compound of formula I according tothis invention is in the approximate range of 5 to 2000 grams of activeingredient (g a.i.) per hectare, with rates of about 50-500 g a.i./haoften achieving satisfactory control. The optimal rate for a specificapplication will depend on the crop(s) under cultivation and thepredominant species of infesting fungus, and readily may be determinedby established biological tests known to those skilled in the art.

In general, the preferred application rate of the N-pyridylanilinecompound is in the approximate range of 20 to 500 g a.i./ha, preferably50-300 g a.i./ha.

The optimal rate for the formula II fungicidal compound will, however,depend on the crop(s) under cultivation and the level of infestation bythe fungus, and can readily be determined by established biologicaltests.

The preferred ratio (by weight) of the compound of formula I to theN-pyridylaniline compound is from 1:20 to 20:1, more preferably fromabout 1:10 to about 10:1, in particular from about 1:2 to about 2:1.

The active compounds may be formulated together in a suitable ratioaccording to the present invention, together with carriers and/oradditives known in the art.

Accordingly, the invention further provides a concentrated liquidfungicidal composition which comprises a carrier and, as activeingredient, at least one compound of formula I as defined above and aN-pyridylaniline compound, in particular fluazinam.

A method of making such a composition is also provided, which comprisesbringing a compound of formula I and a N-pyridylaniline compound intoassociation with at least one carrier. It is also envisaged thatdifferent isomers or mixtures of isomers may have different levels orspectra of activity and thus compositions may comprise individualisomers or mixtures of isomers.

A composition according to the invention preferably contains from 0.5%to 95% by weight (w/w) of active ingredients.

A carrier useful in a composition according to the invention may includeany material which facilitates application of the composition to thelocus to be treated, which locus may, for example, be a plant, seed orsoil, or which will facilitate storage, transport or handling. A carriermay be a solid or a liquid, including material which is normally a gasbut which has been compressed to form a liquid.

The compositions may be manufactured into, e.g., emulsion concentrates,solutions, oil in water emulsions, suspension concentrates,micro-capsules, gels and other formulation types by well-establishedprocedures. These procedures include intensive mixing and/or milling ofthe active ingredients with other substances, such as solvents, solidcarriers, surface active compounds (surfactants), and optionally solidand/or liquid auxilaries and/or adjuvants. The form of application suchas spraying, atomizing, dispersing or pouring may be chosen like thecompositions according to the desired objectives and the givencircumstances.

Solvents may be aromatic hydrocarbons, e.g. Solvesso® 200, substitutednaphthalenes, phthalic acid esters, such as dibutyl or dioctylphthalate, aliphatic hydrocarbons, e.g. cyclohexane or paraffins,alcohols and glycols as well as their ethers and esters, e.g. ethanol,ethyleneglycol mono- and dimethyl ether, ketones such as cyclohexanone,strongly polar solvents such as N-methyl-2-pyrrolidone, orγ-butyrolactone, higher alkyl pyrrolidones, e.g. n-octylpyrrolidone orcyclohexylpyrrolidone, epoxidized plant oil esters, e.g. methylatedcoconut or soybean oil ester and water. Mixtures of different solventsare often suitable.

Pesticidal compositions are often formulated and transported in aconcentrated form which is subsequently diluted by the user beforeapplication. The presence of small amounts of a carrier which is asurfactant facilitates this process of dilution. Thus, preferably atleast one carrier in a composition according to the invention is asurfactant. For example, the composition may contain at two or morecarriers, at least one of which is a surfactant.

Surfactants used in formulations of this invention may be nonionic,anionic, cationic or zwitterionic substances with good dispersing,emulsifying and wefting properties depending on the nature of thecompound according to general formula I to be formulated, and may alsoinclude mixtures of individual surfactants.

The compositions of the invention may, for example, be formulated assolutions, emulsifiable concentrates, emulsions, suspension concentratesand aerosols. Emulsifiable concentrates usually contain, in addition toa solvent or a mixture of solvents, 1 to 80% w/v active ingredient, 2 to20% w/v emulsifiers and 0 to 20% w/v of other additives such asstabilizers, penetrants and corrosion inhibitors. Suspensionconcentrates are usually milled so as to obtain a stable,non-sedimenting flowable product and usually contain 5 to 75% w/v activeingredient, 0.5 to 15% w/v of dispersing agents, 0.1 to 10% w/v ofsuspending agents such as protective colloids and thixotropic agents, 0to 10% w/v of other additives such as defoamers, corrosion inhibitors,stabilizers, penetrants and stickers, and water or an organic liquid inwhich the active ingredient is substantially insoluble; certain organicsolids or inorganic salts may be present dissolved in the formulation toassist in preventing sedimentation and crystalization or as antifreezeagents for water.

Aqueous dispersions and emulsions, for example compositions obtained bydiluting the formulated product according to the invention with water,also lie within the scope of the invention.

Of particular interest in enhancing the duration of the protectiveactivity of the compounds of this invention is the use of a carrierwhich will provide slow release of the pesticidal compounds into theenvironment of a plant which is to be protected as disclosed for exampleby U.S. Pat. No. 5,705,174.

The biological activity of the active ingredient can also be increasedby including an adjuvant in the spray dilution. An adjuvant is definedhere as a substance which can increase the biological activity of anactive ingredient but is not itself significantly biologically active.The adjuvant can either be included in the formulation as a coformulantor carrier, or can be added to the spray tank together with theformulation containing the active ingredient. Preferably, linoleic acidis used as adjuvant.

As a commodity, the compositions may preferably be in a concentratedform whereas the end user generally employs diluted compositions. Thecompositions may be diluted to a concentration down to 0.001% of activeingredient. The doses usually are in the range from 0.01 to 10 kga.i./ha.

Examples of formulations according to the invention are:

    ______________________________________                                        Emulsion Concentrate (EC)                                                     active ingredient                                                                       dimethomorph/fluazinam (1:1 w/w)                                                                   30% (w/v)                                      emulsifier(s)                                                                           Atlox ® 4856 B and Atlox ® 4857 B.sup.1)                                                   5% (w/v)                                                 (mixture containing calcium alkyl                                             aryl sulfonate, fatty alcohol                                                 ethoxylates and light aromatics/                                              mixture containing calcium alkyl aryl                                         sulfonate, fatty alcohol ethoxylates                                          and light aromatics)                                                solvent   Shellsol ® A.sup.2) (mixture of C.sub.9 -C.sub.10                                              to 1000 ml                                               aromatic hydrocarbons)                                              Suspension Concentrate (SC)                                                   active ingredient                                                                       dimethomorph/fluazinam (1:1 w/w)                                                                   50% (w/v)                                      dispersing agent                                                                        Soprophor ® FL.sup.3) (polyoxyethylene                                                         3% (w/v)                                                 polyaryl phenyl ether phosphate                                               amine salt)                                                         antifoaming agent                                                                       Rhodorsil ® 422.sup.3) (nonionic                                                               0.2% (w/v)                                               aqueous emulsion of                                                           polydimethylsiloxanes)                                              structure agent                                                                         Kelzan ® S.sup.4) (Xanthan gum)                                                                0.2% (w/v)                                     antifreezing agent                                                                      Propylene glycol     5% (w/v)                                       biocidal agent                                                                          Proxel ®.sup.5) (aqueous dipropylene                                                           0.1% (w/v)                                               glycol solution containing 20% 1,2-                                           benisothiazolin-3-one)                                              Water                          to 1000 ml                                     ______________________________________                                         .sup.1) Product commercially available from ICI Surfactants                   .sup.2) Product commercially available from Deutsche Shell AG                 .sup.3) Product commercially available from RhonePoulenc                      .sup.4) Product commercially available from Kelco Co.                         .sup.5) Product commercially available from Zeneca                       

A concentrated composition according to the invention preferablycontains from 0.5% to 95% by weight of active ingredients.

In a preferred embodiment, the active ingredients are each added to thetank mix as a solo formulation containing a single active ingredient toform the composition of this invention.

Therefore, the present invention also relates to a kit for thepreparation of a spray mixture consisting of two separate units:

(i) a unit which comprises at least one fungicide of formula I,conventional adjuvants and carriers;

(ii) a unit which comprises at least one N-pyridylaniline compound, inparticular fluazinam, conventional adjuvants and carriers.

In a preferred embodiment, the said kit will consist of two bottles withdispensing means which allow the easy and correct addition ofappropriate amounts of the active ingredients to the tank mix.

For a more clear understanding of the invention, specific examples areset forth below. These examples are merely illustrations and are not tobe understood as limiting the scope and underlying principles of theinvention in any way. Various modifications of the invention in additionto those shown and described herein will become apparent to thoseskilled in the art from the following examples and foregoingdescription. Such modifications are also intended to fall within thescope of the appended claims.

The test results described below demonstrate the enhancement in efficacy(synergy) of the combination of the compounds of formula I andN-pyridylaniline compounds of this invention.

EXAMPLE 1

For this greenhouse study, formulated dimethomorph (500 g/l SC,) andcommercially available formulated fluazinam (500 g/l SC, trade nameSHIRLAN) were used.

Potato var. `Bintje` were grown up in small pots and, after havingobtained a height of approximately 10 cm, were sprayed with 12.5 g ai/haof dimethomorph or fluazinam using the `solo` products, and with thecombination of 12.5+12.5 g ai/ha of dimethomorph+fluazinam (in-tankmixture). The spray volume was equivalent to 400 l/ha into which theproducts were suspended. A track sprayer with an even spray nozzle wasused for the application. Five days after application of the productsthe plants were inoculated with a zoospore suspension of Phytophthorainfestans. The plants were then transferred to a greenhouse cabine inwhich the relative humidity was maintained at around 99-100%.

Disease symptoms (potato late blight) were assessed 11 and 15 days afterapplication (DAT) of the products. The efficacy of the products wascalculated in relation to the untreated plants. The results of thisevaluation are shown in Table I.

                  TABLE I                                                         ______________________________________                                                     11 days       15 days                                                    dose efficacy (%)  efficacy (%)                                       Treatment (g/ha) obtained expected                                                                             obtained                                                                             expected                              ______________________________________                                        dimethomorph                                                                            12.5   25       --     22     --                                    fluazinam 12.5   37       --     27     --                                    dimethomorph +                                                                          12.5   89       53     78     43                                    fluazinam 12.5                                                                ______________________________________                                    

Whereas the `solo` products provided 25 and 22% disease control(dimethomorph) and 37 and 27% disease control (fluazinam) at 11 and 15DAT, the in-tank mixed combination of dimethomorph with fluazinamprovided 89 and 78% disease control at 11 and 15 DAT, respectively. Theefficacy of the combination was clearly higher than could have beenexpected from the additive efficacy of the two products which would havebeen 53 and 43% at 11 and 15 DAT, respectively. Hence, it is clear thatsynergism occurred between dimethomorph and fluazinam. When an adjuvantwas added to the in-tank mixture of dimethomorph plus fluazinam, thesynergism was also observed.

EXAMPLE 2

Effect of fungicidal SC formulations of dimethomorph and fluazinam asactive ingredients in combination with an adjuvant against potato lateblight. The adjuvant is formulated as described in the following Recipe:

    ______________________________________                                        Soprophor 796/B.sup.a)  100     g                                             (ethoxypropoxylated tristyrylphenol)                                          Edenor SB 0.5.sup.b)    to 1000 ml                                            ______________________________________                                         .sup.a) commercially available from RhonePoulenc                              .sup.b) commercially available composition consisting of about 70% by         weight of linoleic acid and about 30% by weight of linolenic acid        

The formulations were applied in a small band on the leaves, 5 daysbefore inoculation. Fungicidal efficacy at 11 days after treatment isshown in table II:

                  TABLE II                                                        ______________________________________                                        treatment      dose (g/ha)                                                                             efficacy (%)                                         ______________________________________                                        dimethomorph + 25        86                                                   fluazinam      25                                                             dimethomorph + 25        94                                                   fluazinam +    25                                                             linoleic acid  500                                                            linoleic acid  500       9                                                    ______________________________________                                    

The 94% efficacy was higher than that predicted according to the Colbyformula (87%).

What is claimed is:
 1. A liquid concentrated fungicidal compositioncomprising a fungicidally acceptable carrier and/or surface active agentand synergistically effective amounts of dimethomorph and fluazinam inan approximate weight ratio of from 1:20 to 20:1.
 2. A composition asclaimed in claim 1, wherein the ratio by weight of dimethomorph tofluazinam is in the approximate range of from 1:10 to 10:1.
 3. Acomposition as claimed in claim 1, wherein the ratio by weight ofdimethomorph to fluazinam is in the approximate range of from 1:2to 2:1.4. A method of controlling the growth of phythopathogenic fungi at alocus which comprises applying to the locus synergistically effectiveamounts of dimethomorph and fluazinam, wherein the application rate ofthe fluazinam at the locus is in the approximate range of from 5 to 2000grams per hectare and the approximate weight ratio of dimethomorph tofluazinam is from 1:10 to 10:1.
 5. The method as claimed in claim 4,wherein said approximate ratio is from 2:1 to 1:2.
 6. A method ofcontrolling the growth of phythopathogenic fungi at a locus whichcomprises applying a composition as claimed in claim 1 to the locus,wherein the application rate of the fluazinam at the locus is in theapproximate range of from 5 to 2000 grams per hectare.
 7. A method ofcontrolling the growth of oomycetes at a locus which comprises applyinga composition as claimed in claim 1 to the locus, wherein theapplication rate of the fluazinam at the locus is in the approximaterange of from 5 to 2000 grams per hectare.
 8. A method for controllingthe growth of oomycetes at a locus, which comprises applyingsynergistically effective amounts of dimethomorph and fluazinam to thelocus in an approximate ratio by weight of from 1:2 to 2:1, wherein theapplication rate of the fluazinam at the locus is in the approximaterange of from 5 to 2000 grams per hectare.
 9. A method according toclaim 8 wherein said ratio is approximately 1:1.
 10. A method accordingto claim 8 further comprising adding a fungicidally enhancing amount oflinoleic acid to the locus.
 11. A method for controlling the growth ofPhytophthora infestens at a locus which comprises applyingsynergistically effective amounts of dimethomorph and fluazinam to thelocus in an approximate weight ratio of from 2:1 to 1:2.